Generally, light-sensitive materials have silver halide emulsion layers sensitive to the three primary colors of red, green and blue, respectively, and a dye image is reproduced by a method wherein three kinds of color formers (couplers) contained in emulsion layers are developed to form colors having a relation of complementary colors to the light to which the emulsion layers are sensitive. Namely, a dye image is reproduced by subtractive color photography. A dye image obtained by photographically processing the light-sensitive material comprises generally an azomethine dye or an indoaniline dye formed by the reaction of the oxidants of aromatic primary amine color developing agents with couplers. The thus-obtained photographic color image is not always stable against light, heat and moisture, and when the color image is exposed to light over a long period of time or stored under high temperature and humidity conditions, the dye image is faded or discolored, and the image quality thereof is deteriorated.
The fading or discoloration of the image is a serious problem in recording materials. To eliminate this problem, there have been proposed the development of couplers giving a dye image having high fastness, the use of anti-fading agents, and the use of ultraviolet light absorbers to prevent the image from being deteriorated by ultraviolet light.
Examples of the anti-fading agents conventionally known include hydroquinones, hindered phenols, catechols, gallic esters, aminophenols, hindered amines, chromanols, indenes and ethers or esters obtained by silylating, acylating or alkylating the phenolic hydroxyl group of these compounds and metal complexes.
Further, sulfides having a specific structure, sulfoxides, sulfur-containing heterocyclic compounds and tetrahydrothiopyran compounds having a specific structure are proposed in U.S. Pat. Nos.4,540,658, 4,880,733, 4,704,350 and 5,104,781, U.K. Patent 1,410,846, JP-A-63-43146 (the term "JP-A" as used herein means an "unexamined published Japanese patent application"), JP-A-63-149644, JP-A-62-103642, European Patent Laid-Open Nos. 178,794, 310,551 and 310,552.
These compounds have certainly an effect of preventing dye images from being faded or discolored. However, these compounds are insufficient to cope with the demand of customers which require a higher image quality, and an excellent effect demanded by color photograph can not be obtained so far.